1. Technical Field
The present invention relates to liquid ejecting apparatuses, and more specifically, to a configuration of liquid supplying flow channels through which liquid is supplied to liquid ejection heads.
2. Related Art
Generally, ink jet printers are widely known as a type of liquid ejecting apparatuses that eject liquid onto a medium. In these printers, printing is performed by ejecting ink (liquid) from ink cartridges (liquid storage containers) through nozzles which are formed on a liquid ejection head onto a medium (for example, sheet of paper). Recently, pigment ink has been sometimes used in these printers in order to achieve high-quality printing.
However, pigment ink has a problem in that pigment particles in the ink solvent settle out over time, resulting in uneven concentration of the pigment ink, thereby shades of the printed colors being slightly changed. In particular, when the pigment particles move through a long liquid supplying flow channel from the ink cartridge to the liquid ejection head, the sedimentation of pigment particles may occur in the liquid supplying flow channel. Accordingly, even if ink is stirred in the ink cartridge, it is difficult to prevent the color shades of pigment ink from being changed without reducing the unevenness in concentration of the pigment ink in the liquid supplying flow channel from the ink cartridge to the liquid ejection head.
JP-A-2010-188590 discloses a technique for stirring ink in the liquid supplying flow channel, in which a pressure and vacuum pump is used to generate a pressure variation inside the liquid supplying flow channel (passage), thereby causing a movable wall which is a part of the wall of the liquid supplying flow channel to be displaced. This displacement of the movable wall generates a flow of ink so that ink is stirred in the liquid supplying flow channel.
In the technique according to JP-A-2010-188590, however, the pressure and vacuum pump is provided as an additional device for generating a pressure variation in the liquid supplying flow channel so as to stir the ink, which may lead to large-sized printer or complicated configuration. Accordingly, a technique is needed for stirring ink in the liquid supplying flow channel without using an additional device.